2,537 research outputs found

    Chinese CLIP: Contrastive Vision-Language Pretraining in Chinese

    Full text link
    The tremendous success of CLIP (Radford et al., 2021) has promoted the research and application of contrastive learning for vision-language pretraining. In this work, we construct a large-scale dataset of image-text pairs in Chinese, where most data are retrieved from publicly available datasets, and we pretrain Chinese CLIP models on the new dataset. We develop 5 Chinese CLIP models of multiple sizes, spanning from 77 to 958 million parameters. Furthermore, we propose a two-stage pretraining method, where the model is first trained with the image encoder frozen and then trained with all parameters being optimized, to achieve enhanced model performance. Our comprehensive experiments demonstrate that Chinese CLIP can achieve the state-of-the-art performance on MUGE, Flickr30K-CN, and COCO-CN in the setups of zero-shot learning and finetuning, and it is able to achieve competitive performance in zero-shot image classification based on the evaluation on the ELEVATER benchmark (Li et al., 2022). We have released our codes, models, and demos in https://github.com/OFA-Sys/Chinese-CLI

    Methods used to study the oligomeric structure of G protein-coupled receptors

    Get PDF
    G-protein coupled receptors (GPCRs), which constitute the largest family of cell surface receptors, were originally thought to function as monomers, but are now recognized as being able to act in a wide range of oligomeric states and indeed, it is known that the oligomerization state of a GPCR can modulate its pharmacology and function. A number of experimental techniques have been devised to study GPCR oligomerization including those based upon traditional biochemistry such as blue-native polyacrylamide gel-electrophoresis (BN-PAGE), co-immunoprecipitation and protein-fragment complementation assays, those based upon resonance energy transfer, fluorescence resonance energy transfer (FRET), time-resolved FRET, FRET spectrometry and bioluminescence resonance energy transfer (BRET). Those based upon microscopy such as fluorescence recovery after photo-bleaching (FRAP), total internal reflection fluorescence microscopy (TIRF), spatial intensity distribution analysis (SpIDA) and various single molecule imaging techniques. Finally with the solution of a growing number of crystal structures, X-ray crystallography must be acknowledged as an important source of discovery in this field. A different, but in many ways complementary approach to the use of more traditional experimental techniques, are those involving computational methods which possess obvious merit in the study of the dynamics of oligomer formation and function. Here we summarize the latest developments which have been made in the methods used to study GPCR oligomerization and give an overview of their application

    Progress in surgical treatment of macular hole retinal detachment in high myopic

    Get PDF
    Macular hole retinal detachment(MHRD)mainly occurs in high myopic eyes with posterior scleral staphyloma and always causes severe visual impairment. The pathogenesis of MHRD in high myopic eyes is still unclear. It is generally believed that it involves various complex traction. A variety of surgical methods have been tried to remove retina tractionin order to achieve retina reattachment and macular hole closure. This article reviews the current surgical methods and progress of MHRD in high myopic eyes

    Depletion of OLFM4 gene inhibits cell growth and increases sensitization to hydrogen peroxide and tumor necrosis factor-alpha induced-apoptosis in gastric cancer cells

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Human olfactomedin 4 (OLFM4) gene is a secreted glycoprotein more commonly known as the anti-apoptotic molecule GW112. OLFM4 is found to be frequently up-regulated in many types of human tumors including gastric cancer and it was believed to play significant role in the progression of gastric cancer. Although the function of OLFM4 has been indicated in many studies, recent evidence strongly suggests a cell or tissue type-dependent role of OLFM4 in cell growth and apoptosis. The aim of this study is to examine the role of gastric cancer-specific expression of OLFM4 in cell growth and apoptosis resistance.</p> <p>Methods</p> <p>OLFM4 expression was eliminated by RNA interference in SGC-7901 and MKN45 cells. Cell proliferation, anchorage-independent growth, cell cycle and apoptosis were characterized in vitro. Tumorigenicity was analyzed in vivo. The apoptosis and caspase-3 activation in response to hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) or tumor necrosis factor-alpha (TNF α) were assessed in the presence or absence of caspase inhibitor Z-VAD-fmk.</p> <p>Results</p> <p>The elimination of OLFM4 protein by RNA interference in SGC-7901 and MKN45 cells significantly inhibits tumorigenicity both in vitro and in vivo by induction of cell G1 arrest (all P < 0.01). OLFM4 knockdown did not trigger obvious cell apoptosis but increased H<sub>2</sub>O<sub>2 </sub>or TNF α-induced apoptosis and caspase-3 activity (all P < 0.01). Treatment of Z-VAD-fmk attenuated caspase-3 activity and significantly reversed the H<sub>2</sub>O<sub>2 </sub>or TNF α-induced apoptosis in OLFM4 knockdown cells (all P < 0.01).</p> <p>Conclusion</p> <p>Our study suggests that depletion of OLFM4 significantly inhibits tumorigenicity of the gastric cancer SGC-7901 and MKN45 cells. Blocking OLFM4 expression can sensitize gastric cancer cells to H<sub>2</sub>O<sub>2 </sub>or TNF α treatment by increasing caspase-3 dependent apoptosis. A combination strategy based on OLFM4 inhibition and anticancer drugs treatment may provide therapeutic potential in gastric cancer intervention.</p

    Draft Genome Analysis Offers Insights Into the Mechanism by Which Streptomyces chartreusis WZS021 Increases Drought Tolerance in Sugarcane

    Get PDF
    Drought directly affects sugarcane production. Plant growth-promoting bacteria have gained attention as growth promoters of plants under abiotic stresses. The present study focused on genome assessment of the plant-beneficial endophyte Streptomyces chartreusis WZS021 and its vital role in sugarcane plants under drought stress. Based on in vitro plant growth-promoting trait analyses, WZS021 had multiple abilities, including tolerance to drought and production of 1-aminocyclopropane-1-carboxylic deaminase, siderophores, and indole acetic acid. We confirmed root colonization of sugarcane transplants by WZS021 by a sterile sand assay and scanning electron microscopy. Plants inoculated with strain WZS021 had a positive influence on the root parameters such as length and biomass when compared to the control plants. A comparative study of the responses of two sugarcane varieties (ROC22 and B8) to different levels of drought stress in the presence or absence of WZS021 was conducted by assessing the plant chemistry. The expression of antioxidants in sugarcane leaves varied with water stress level. WZS021 inoculation improved the contents of chlorophyll, proline, and phytohormones, revealing some potential for the mechanisms by which this strain improves drought tolerance in sugarcane plants. We identified several genes that might be involved in the plant growth- and drought tolerance-promoting effects of this strain

    Therapeutic Effects of Traditional Chinese Medicine on Spinal Cord Injury: A Promising Supplementary Treatment in Future

    Get PDF
    Objective. Spinal cord injury (SCI) is a devastating neurological disorder caused by trauma. Pathophysiological events occurring after SCI include acute, subacute, and chronic phases, while complex mechanisms are comprised. As an abundant source of natural drugs, Traditional Chinese Medicine (TCM) attracts much attention in SCI treatment recently. Hence, this review provides an overview of pathophysiology of SCI and TCM application in its therapy. Methods. Information was collected from articles published in peer-reviewed journals via electronic search (PubMed, SciFinder, Google Scholar, Web of Science, and CNKI), as well as from master’s dissertations, doctoral dissertations, and Chinese Pharmacopoeia. Results. Both active ingredients and herbs could exert prevention and treatment against SCI, which is linked to antioxidant, anti-inflammatory, neuroprotective, or antiapoptosis effects. The detailed information of six active natural ingredients (i.e., curcumin, resveratrol, epigallocatechin gallate, ligustrazine, quercitrin, and puerarin) and five commonly used herbs (i.e., Danshen, Ginkgo, Ginseng, Notoginseng, and Astragali Radix) was elucidated and summarized. Conclusions. As an important supplementary treatment, TCM may provide benefits in repair of injured spinal cord. With a general consensus that future clinical approaches will be diversified and a combination of multiple strategies, TCM is likely to attract greater attention in SCI treatment

    Use of ELISpot assay to study HBs-specific B cell responses in vaccinated and HBV infected humans

    Get PDF
    Hepatitis B surface antibody (HBsAb) plays a critical role in protecting against infection of hepatitis B virus (HBV) and were extensively studied in literature. At the same time, the status of hepatitis B surface antigen (HBs)-specific B cells in both vaccinated and HBV infected people received limited attention. In the current study, we adopted a highly specific B-cell Enzyme Linked ImmunoSpot (ELISpot) assay to analyze HBs-specific B cells in various clinical settings: healthy individuals with the history of HBV vaccination before and after receiving an extra HBV vaccine boost, people chronically infected with HBV (CHB) in various clinical stages, with or without a particular type anti-viral treatment, or whether receiving a dose of HBV vaccine. In all of these cases, B-cell ELISpot assay was used effectively in enumerating the frequency of HBs-specific B cells. While the focus of the current report was to establish the utility of this assay for HBV research, a number of interesting observations were made in this pilot study based on the profiles and dynamics of HBs-specific B cells in various conditions. Such information is useful to guide the future work in designing novel therapeutic strategies against CHB
    corecore